U.S. currency that does not pass inspection is removed for destruction. This creates a problem for the printers, as the serial numbers are automatically done by computer in the printing process. There were only two options: spend 3 days reprogramming the computer every time a note or sheet didn't pass, or create replacement notes - issued to replace a damaged, destroyed or lost note.

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"Playing Card" money was a type of emergency issue used in Canada between the late 17th century and mid-18th century by French colonial authorities. They actually cut up playing cards and marked them as currency.

-- Lee the Stamp Gal

An early Canadian banknote vignette of Queen Elizabeth II supposedly contains a likeness of the devil in her hair. Of course, the Queen's hairdo was changed, due to the unfavorable publicity once the word got out.

-- Lee the Stamp Gal

Some business schools in the late 1800's made their own fake "banknotes" in order to use in the classroom as teaching aids for business practices, and handling money. These are rare now.

-- Lee the Stamp Gal

In the 19th century, banks issued the money. Sometimes currency became non-negotiable or worthless as money because the issuing bank went out of business. Sometimes a bank, called a wildcat bank, was never really in business. They issued currency as a money-making scheme.

-- Lee the Stamp Gal

There is currency from the French Revolution in the 1790's called an assignat, which was not backed by gold or silver. It was backed by seized Church property.

-- Lee the Stamp Gal

This is a slang term for a certain German 10,000 mark note design. It's referred to as the "Vampire Note" because, if you turn the bill a certain way, you can see a vampire biting the neck of the German worker pictured. This was supposedly done on purpose, in protest of the government "sucking the common people dry" and is sometimes said to have been a comment on the WWI & pre WWII government figures of Germany.

-- Lee the Stamp Gal